Marinate all the potato and capsicum in curd (curd enhances the taste). Add salt, red chili powder, turmeric powder, jeera powder, kasuri methi, anardana. Keep aside.
In a pan, heat the oil and fry sliced onions till golden brown. Please be careful and do not burn, trick is to switch off the heat once it starts turning reddish. Remove from the oil and keep aside.
Now, on low flame, saute the masalas and ¾th quantity of fried onions, marinated vegetables. Add ginger-garlic paste paste. Simmer for about 2 minutes and add tomatoes and biryani masala. Stir for 1-2 minutes. The vegetables should be half cooked.
Add the green peas. I added corn too as I had them. Stir for about half a minute and add a part of mint and coriander leaves. Now, gently layer the cooked rice and sprinkle the remaining fried onions, coriander leaves and min leaves on them evenly. Pour the kesar milk evenly at this stage. I also add about 2-3 tsp of oil that we used in frying onions, it gives a nice aroma to the rice.
Dum-process: Sprinkle about 2-3 tbsp of water that we kept aside from draining cooked rice. Cover with a tight lid and seal the covering with the dough. Now, for about 1-2 minutes keep the heat on high flame and then let it cook slowly on low flame. You may keep a tava below your pot so that the heat is evenly distributed. This allows all the aromas and flavors to seep into the rice nicely.
After 10-12 minutes exactly, switch off the flame and remove the seal carefully with a knife. Check the rice, you will notice that the water that we sprinkled is gone, rice is perfectly cooked, vegetables are intact, didn't overcook or burn and everything looks delicious.
Serving: Making biryani is not as tough, but a lot of people screw it up at the time of serving. So make sure you take out the biryani with a flat and thin spatula and remove it from pan in layers from the side. Do not mix. Garnish with mint leaves, dry fruits if you want to add, fried onions. Serve with raita and pickle. Ta-da-da!! You're now never going to order a biryani from outside..!